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package org.apache.juneau.httppart;

import org.apache.juneau.*;
import org.apache.juneau.remoteable.*;

/**
 * Interface used to convert POJOs to simple strings in HTTP headers, query parameters, form-data parameters, and URI
 * path variables.
 * 
 * <p>
 * The following default implementations are provided:
 * <ul class='doctree'>
 * 	<li class='jc'>{@link org.apache.juneau.httppart.UonPartSerializer} - Parts encoded in UON notation.
 * 	<li class='jc'>{@link org.apache.juneau.httppart.SimpleUonPartSerializer} - Parts encoded in UON notation, but
 * 		strings are treated as plain-text and arrays/collections are serialized as comma-delimited lists.
 * 	<li class='jc'>{@link org.apache.juneau.httppart.SimplePartSerializer} - Parts encoded in plain text.
 * </ul>
 * 
 * <p>
 * This class is used in the following locations:
 * <ul>
 * 	<li class='ja'>{@link FormData#serializer()}
 * 	<li class='ja'>{@link FormDataIfNE#serializer()}
 * 	<li class='ja'>{@link Query#serializer()}
 * 	<li class='ja'>{@link QueryIfNE#serializer()}
 * 	<li class='ja'>{@link Header#serializer()}
 * 	<li class='ja'>{@link HeaderIfNE#serializer()}
 * 	<li class='ja'>{@link Path#serializer()}
 * 	<li class='ja'>{@link RequestBean#serializer()}
 * 	<li class='jc'><code>RestClientBuilder.partSerializer(Class)</code>
 * </ul>
 * 
 * <p>
 * Implementations must include either a public no-args constructor or a public constructor that takes in a single
 * {@link PropertyStore} object.
 */
public interface HttpPartSerializer {

	/**
	 * Represent "no" part part serializer.
	 * 
	 * <p>
	 * Used to represent the absence of a part serializer in annotations.
	 */
	public static interface Null extends HttpPartSerializer {}

	/**
	 * Converts the specified value to a string that can be used as an HTTP header value, query parameter value,
	 * form-data parameter, or URI path variable.
	 * 
	 * <p>
	 * Returned values should NOT be URL-encoded.
	 * 
	 * @param type The category of value being serialized.
	 * @param value The value being serialized.
	 * @return The serialized value.
	 */
	public String serialize(HttpPartType type, Object value);
}
